Which of the following results is returned by the JavaScript operator "typeof" for the keyword "null"?

Which method is used to add and/or remove elements from an array and modify them in place?

Which function of the Object constructor with regard to JavaScript 1.8 returns the array of names of only enumerable properties of the given object?

In relation to object oriented JavaScript, which option can be used as the value of F.prototype?

In relation to sealing an object globally, which methods returns true if adding, removing, and changing properties is forbidden and all the current properties are configurable: false, writable: false?

Using DATE object which call a function based on elapsed time?

Which are true regarding JavaScript and multi-threading/concurrency?

Which code snippet will trigger an input type='file' attribute when an element with a 'newbtn' ID is clicked? Upload

Which will determine if the user's browser is named 'Netscape'?

Which is used to solve the problem of enumerations in JavaScript?

Which is an invalid function declaration?